Rail bond



y 1950 w. F. CLARK 2,508,225

RAIL BOND Filed Oct. 23, 1946 Atlorney Patented May 16, p 1950 RAIL BOND William F. Clark, Mansfield, Ohio, assignor to The Ohio Brass Company, Mansfield, Ohio, a corporation of New Jersey Application October 23, 1946, Serial No. 705,151

2 Claims. (Cl. 287-203) This invention relates to bonds to electrically connect the adjacent ends of rails and has particular reference to connecting rails of tracks formin a part of a signal system.

One object of this invention is to connect the rails by a low resistance path such as obtained when the path is entirely of copper.

Another object is to provide a bond which will withstand the abuse to which it is subjected in normal service such as, temperature changes, corrosion, vibration, resistance to impact of dragging equipment, etc.

7 Another object is to provide a bond in which no heat is employed in the assembly of its parts or in its installation.

A further object is to provide a bond having terminals which may be installed equally well by a hammer or a compressor and improve the grip or hold of the terminals to the rail.

Still another object of this invention is to provide a bond which requires less manual effort and skill to provide a reliable union with the rails. A still further object is to provide a rail bond having terminals which will still provide a satisfactory connection with the rails when driven by a hammer at an angle to the axis of the termlnal.

This invention will be better understood by reference to the following description taken in conjunction with the accompanying drawing, and particularly pointed out in the claims.

In the drawing:

Figure 1 is a side view of this invention.

Figure 2 is a top view of the invention of Figure 1.

Figures 3, 4 and 5 are side, end and face views respectively of a portion of the terminal member.

Figures 6 and 7 are side and end views respectively of a plug or insert used with the terminal.

Figure 8 is a view in section on the line 8'-8 of Figure 1 showing a partial assembly of the terminal parts before the assembly has been completed.

Figure 9 is a view in section on the line 9-9 of Figure 2.

Figure 10 is an enlarged view in section showing the bond terminal positioned in a rail opening and before final installation.

Figure 11 is a section as in Figure 10 after the terminal has been applied by impact as by hammer blows or by compression.

cable of the required capacity and length. It is found that a cable formed from bronze such as phosphor bronze gives sufficiently low resistance and at the same time has the property of withstanding vibration much better than a cable of copper. For some purposes a cable of steel wires may be found useful.

The terminals are formed of two members, a body member 2 and plug or insert 3.

The body member is preferably of steel and comprises a head portion 4, a, stud portion 5 and a sleeve portion 6. The terminal is provided with an openin 1 which extends through the sleeve portion 6 and a portion of the head to receive an end of the member I and a second opening 8 which extends axially through the stud portion 5 and intersects the opening 1.

The head portion has an external flattened area 9 normal to and in alignment with the axis of the stud portion 5 while the lower end of the stud portion 6 has a beveled face I 11 extending inward and upward.

The plug or insert 3 is formed from copper and then annealed and comprises a shank portion H, a button portion l2 and axially extending ribs l3 along the shank. The shank portion II and ribs l3 are proportioned to extend into the opening 8 and the button portion I2 to project therefrom.

The button portion 12 of the plug 3 has a beveled portion l4 which conforms to and cooperates with the beveled portion Ill on the stud portion and also has a beveled or cone shaped end face Hi.

The bond is assembled by first applying to each end of the cable I a body member 2 by positioning the cable end within the opening I. A plug or insert 3 is then positioned in the opening 8 of each stud 5 (see Fig. 8).

The small ribs l3 aid only in assembly of the body member and plug or insert by hand whereby the friction is sufficient to hold these parts together until final assembly may be effected (see Fig. 9).

After the preliminary assembly just mentioned the 3 parts are subjected cold to extremely high pressure in a die and sufiicient to force the sleeve and head portions'into intimate engagement with the cable end and to force the end face of the shank H into secure engagement with the cable end. At the same time the beveled face M of the button portion I2 is seated against the beveled face In and the stud portion 5 forced into contact with the shank H of the insert 3 (see Fig. 9) and the stud and button portions brought to their re- 3 quired size both as to diameter and length, which is very important in this type of bond.

Up to date, the exposed cone shaped ends of the terminals on bonds for the purpose of applicants bond have been given a taper the same as that of the end wall of the opening in the rail for the bond. This taper is a standard of substantially 120 degrees included angle and when the bond terminal is inserted in the opening the entire end face of the terminal corresponds to and engages the entire end face or surface of the opening since the included angle of each is the same.

It has been found however improved results may be secured by changing such angular relation as described above between the terminal and the end wall of the opening as for instance (1) the grip or hold on the side walls of the opening increased, (2) the installation made easier and (3) the reliability of installation enhanced.

By changing the bevel of the end face l5 of the terminal or button l2 such that the included angle thereof is less than that of the conical end face of the rail opening the above improved results will be secured.

In Figure is shown the improved bond terminal inserted in an opening It in a rail head I! and the conical end wall. l8 of the opening having the angle produced by a. standard drill namely 120' degrees. The face of the terminal forms a cone shaped end with an included angle less thanl that of the conical end" face It of the opening 36 In. use the rail head is usually drilled with the opening 16 in which "a is about inch diameter and b about A; inch deep. These dimensions may be varied as required.

The length of the stud 5 and plug' 3 is such that when the terminal is first inserted in the opening I S, the stud will project a predetermined amount from the rail face as shown in Figure 10.

The variation in the angles of the conical end wall 18 and the conicalface I5 will form a space or' void i9 therebetween when the terminal is inserted inthe opening It with the apex 20 of the plug positioned against the apex 2| of the end wall it.

When the terminal has been positioned in the rail opening a few relatively light impact blows onthe face 9' of the body member 2- will properly ai'hx'the terminal to the' rail.

As the impact force' is applied, and since the apex 22 of the soft annealed copper plug 3 engages the apex 2! of the steel rail, the first blow of the hammer produces an infinitely high initial pressure on the apex 28' of the plug. Since the apex is a point or has a very small area the applied impact force will be largely concentrated initially on the tip of the plug S'andthen extend throughout the plug 3.

'Itappears that with the first or second impact of the hammer the metal in' the button i 2 will be forced tightly against and'conform to the conical end wall It of the opening It, thereby eliminating the space l9, and simultaneously the button 12 of the soft plug will be expanded laterally thereby engaging the side wall of the opening IB and the metal of the plug within the stud 5 will expand thereby forcing the wall 22 into engagement with the side wall of the. opening thus effecting the required close grip or hold between the terminal and rail (Fig. 11). The coacting surfaces I0 and ['4' will aid in effecting the said grip or hold.

The initial projection of the stud from the rail face will permit sufficient movement of the terminal to force the stud and plug into the rail opening a sufficient amount to secure the above effect.

It has also been found that with the above construction that even when the hammer blows are misapplied as for instance to the edge of the area 9 at an angle of as much as 23 degrees to the axis of the terminal as indicated by the dotted lines ccx that a dependable and reliable installation is secured.

The apex 2! may be a point or it may have some area. It has been found that the included angle of the conical surface It may, merely as an example, be about degrees thereby providing' space 19 of about 15 degrees.

Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:

1. A bond, for connecting a pair of rails hav ing bond-receivin g cavities with substantially cylindrical side walls and bottom walls of about concave conicity, comprising in combination a terminal having a cab1e-end-receiving. recess and an insert-receiving recess, a cable in the first said recess and an insert in the second recess, one end of said insert bearing against the cable in said terminal and the opposite end of said insert projecting from said terminal and having an end surface of convex conical shape with an included angle substantially less than 129, the insert-carrying part of said terminal being adapted to be positioned in one of said rail cavities with the convex conical end surface of the insert in contact with the apex of the bottom Wall of said cavity and the insert being expansible into contact with the surfaces of the cavity by forces applied to the exposed portion of the terminal.

2. A bond, for connecting a pair of rails having bond-receiving cavities with substantially cylindrical side walls and bottom walls of about 120 concave conicity, comprising in combination: a terminal having a cable-end-receiving recess and an insert-receiving recess, a cable in the first said recess and an insert in the second recess, one end of said. insert bearing against the cable in said terminal and the opposite end of said insert projecting from said terminal andhaving an end surface of convex conical shape with an. included angle of. approximately 90, the insert-carrying part of said terminal being adaptedto be positioned in one of said rail cavities with the convex conical endv surface of the insert in contact with the apex. of the bottom wall of said cavity and the insert bein expansible into contact with the surfaces of the cavity by forces applied to the exposed portion of the terminal.

WILLIAM F. CLARK.

REFERENQES CITED The following references are of record in the file of this patent:

UNITED STATES PATENT-S Number Name Date 290,229 Griest Dec. 18, 1883 1,704,228 Tibbetts Mar. 5, 1929 2,155,217 Bovard Apr. 18, 1939 2,166,655 Chandler Jul I8, 1939 2,181,467 Stolnacks Nov. 28, 1939 2,237,329 Bischof Apr. 3', 1941 2,283,095 Sabol May 12, 1942 2,306,642 Sabol Dec. 29, 1942 2,415,232 Brock Feb. 4,. 1947 

